1. Field of Invention
This invention relates to a baling apparatus, and more particularly to a baler having a planetary gear train drivingly attached to a flywheel and drivingly attached relative to a plunger assembly to transmit power between the flywheel and the plunger assembly to drive a plunger head.
2. Description of Related Art
Conventional square hay balers are typically driven by a power-take-off system of an agricultural tractor and are driven along a field by the tractor. Conventional balers include a reciprocating plunger that slides into and out of a baling chamber. As the chamber receives loose hay material, the plunger slides into the chamber during a compaction stroke to compress the loose hay material into the form of a bale. Such balers also typically include a gearbox that transmits power to the reciprocating plunger and includes intermeshing gears.
Prior art hay balers require the application of large cyclical forces to the plunger. Forces are relatively high during the compaction stroke, and particularly when loose material is being compacted. However, during a plunger retraction stroke and during other parts of the compaction stroke, the forces required to move the plunger are generally much lower. Because this highly cyclical power requirement can be harmful to the power-take-off system and drive train of the tractor, prior art hay balers also include a flywheel that operates as an energy buffer.
However, prior art square hay balers have certain deficiencies. For instance, the relatively high inertia of conventional baler flywheels causes startup of the baler to be difficult. In particular, engagement of the power-take-off to start the baler can cause stalling of the tractor engine. The use of a flywheel in prior art balers to eliminate exposure of the power-take-off to harmful cyclical loading is only somewhat effective.